Fixed error when cropping images

Fixed notifications not being sent if the image of the new website state was too big for telegram to handle as an image. Now images too large will be sent as files instead

Author: iComputerfreak

urlwatcher/Sources/urlwatcher/Functions.swift

@@ -58,17 +58,74 @@ func cropScreenshot(path: String, output: String? = nil, x: Int, y: Int, width:
 
     return try bash("convert", arguments: [
         path,
-        "-crop", "\"\(width)x\(height)+\(x)+\(y)\"",
+        "-crop", "\(width)x\(height)+\(x)+\(y)",
         output ?? path
     ])
 }
 
+func imageSize(path: String) throws -> (width: Int, height: Int) {
+    let pipe = Pipe()
+    // Sample Output:
+    // PNG image data, 2938 x 16300, 8-bit/color RGBA, non-interlaced
+    try bash("file", arguments: [path, "-b"], standardOutput: pipe)
+    
+    let outputData = pipe.fileHandleForReading.readDataToEndOfFile()
+    guard let outputString = String(data: outputData, encoding: .utf8) else {
+        return (0, 0)
+    }
+    
+    let components = outputString.components(separatedBy: ", ")
+    guard components.count >= 2 else {
+        return (0, 0)
+    }
+    
+    let sizeComponents = components[1].components(separatedBy: "x").map({ $0.trimmingCharacters(in: .whitespaces) })
+    guard sizeComponents.count == 2 else {
+        return (0, 0)
+    }
+    guard let width = Int(sizeComponents[0]), let height = Int(sizeComponents[1]) else {
+        return (0, 0)
+    }
+    
+    return (width, height)
+}
+
 func sendTelegramMessage(_ message: String, to chatID: Int, image: String? = nil, file: String? = nil) throws {
     var arguments: [String] = [
         "-t", telegramBotToken!,
         "-c", "\(chatID)"
     ]
     if let image = image {
+        // https://core.telegram.org/bots/api#sendphoto
+        // > The photo must be at most 10 MB in size.
+        // > The photo's width and height must not exceed 10000 in total.
+        // > Width and height ratio must be at most 20.
+        // If any of these requirements are not met, send the image as a file
+        let attr = try fileManager.attributesOfItem(atPath: image)
+        // File size in MB
+        var fileSize = attr[.size] as? Float ?? 0
+        fileSize /= 1024 * 1024
+        // Make sure the file is under the 10 MB limit (plus 0.1 MB extra)
+        guard fileSize < 9.9 else {
+            try sendTelegramMessage(message, to: chatID, file: image)
+            return
+        }
+        
+        let imSize = try imageSize(path: image)
+        guard imSize.width <= 10_000 && imSize.height <= 10_000 else {
+            try sendTelegramMessage(message, to: chatID, file: image)
+            return
+        }
+        
+        if imSize.width != imSize.height {
+            // Width and height ratio = max / min
+            guard max(imSize.width, imSize.height) / min(imSize.width, imSize.height) <= 20 else {
+                try sendTelegramMessage(message, to: chatID, file: image)
+                return
+            }
+        }
+        
+        // If all requirements are met, we can send the image
         arguments.append(contentsOf: ["-i", image])
     }
     if let file = file {